Well. That theory would go a long way in explaining why the Unaka Mountains that border a small area on the Northeastern tip of the Smoky Mountains in Tennessee have highly metamorphosed mafic lava.
Much to consider.
Lin
--- In geology2@yahoogroups.com, Kim Noyes <kimnoyes@...> wrote:
>
> It's also probably/nearly certainly a Hot Spot/Mantle Plume ...
Hotspot iffy and "mantle plume" afraid not and none associated with the mid-oceanic ridge of the Atlantic ocean even though much of the magma is derived from the mantle. The last "active" mantle plume in the Atlantic basin,( and this is a debated topic amongst earth scientist if it was in fact a mantle plume), formed the island of Bermuda --as a short-lived, last sputter of a minor plume which has arose mid-North American Plate and traveled deeply under the Appalachian chain during the Cretaceous. Iceland has the happenstance and owes its existence to the mid-oceanic rift and past lower sea-levels. Iceland is one of the few spots on earth where a divergent boundary lies above sea level.
We there a "mantle plume" under Iceland there would be highly mafic( vs felsic) lava like what is found in Hawaii. Instead, the Icelandic lava has a high component of hydrated crustal rock in the melt leading to the high ash ryolitic-trending eruptions we see today.
Eman
--
Got Penguins?
Penguin News Today
The Science of Penguins
Gentoo Penguins of Gars O'Higgins Station, Antarctica
Wolves & Werewolves/Science, Myth & News
http://canislupus101.blogspot.com/
http://dances-with-werewolves.blogspot.com/
http://throughgoldeneyes.blogspot.com/
__._,_.___
Your email settings: Individual Email|Traditional
Change settings via the Web (Yahoo! ID required)
Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured
Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe
__,_._,___
No comments:
Post a Comment